The present invention relates to a shutter speed setting and display apparatus for use with a single-lens reflex camera.
In the single-lens reflex camera, when an appropriate exposure is obtained by changing the shutter speed with its diaphragm fixed, namely in a diaphragm priority mode, the shutter speed is usually changed while looking into a viewfinder of the camera, and conventionally, a shutter speed setting and display apparatus is designed in such a manner that, the moment a shutter speed is set manually by a shutter dial, the set shutter speed is displayed in the first display apparatus of the viewfinder and, the moment a shutter speed is automatically set by measuring the brightness of a subject with an exposure measurement circuit, the thus set shutter speed is displayed in the second display apparatus of the viewfinder, so that the manually set shutter speed is then made to coincide with the shutter speed set by the exposure measurement circuit. In a shutter speed setting and display apparatus of this type, it is convenient that the manually set shutter speed is known from the first display apparatus and that the shutter speed set by the exposure measurement circuit is known from the second display apparatus. The shutter speeds however are displayed by use of two display apparatuses. This makes the shutter speed setting apparatus complicated in its mechanism and expensive.
Furthermore, in the conventional shutter speed setting and display apparatus, the shutter speed is changed by rotating the shutter dial and the operation of the shutter dial is a different kind of operation from the operation of depressing a shutter release button. Therefore, the photographer sometimes lets a good shutter chance go due to the incapability of moving his fingers smoothly in operation. Moreover, in such shutter speed setting and display apparatus, supposing it is designed so as to select 15 different shutter speeds, the number of wires connecting the shutter dial to the body of the shutter speed setting and display apparatus amounts to 15 and goes as high as 16, including a common terminal. Therefore, the pins for an integrated circuit contained in the body of the shutter speed setting and display apparatus become too many so that the apparatus becomes expensive. Furthermore, in the camera of the above-mentioned type, when a subject is dark, a stroboscope is employed wherein the stroboscope is synchronized with the shutter of the camera. The flashlight source of the stroboscope however, cannot be synchronized in the whole range in which the shutter speed setting is possible. Therefore, in the case where the shutter speed is manually set, the shutter speed has to be set by checking the range in which the synchronizing of the flashlight source is possible. This is inconvenient in operating the camera.
Occasionally, there is a fear that the shutter speed is set outside the synchronizing range of the flashlight without checking the range. In such a case, a poor photographing occurs since the flashlight source does not synchronize with the shutter.